Do I need a Many to Many Relationship?

I would like to build a cost estimator table where macros are set up for estimates.  I have two tables: Table 1. Estimate Components (ex. floor cover, tile) and Table 2. Rooms (ex. Living Room). I would like have the capability of creating macros for rooms and adding estimate components from the Estimate Components table using a record picker. Each estimate component would be related to multiple estimates.  The end user would select the room macro they would like to use and simply modify the related components to create an estimate.

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Brad Felten
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